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Epsom Salt for Cucumbers: When And How To Apply?

Living without cucumbers is difficult, isn’t it? The vine plant belonging to the gourd family finds multiple uses in our home and kitchen. Whether making your favorite green salad or your DIY Face Mask, cucumbers are irreplaceable.

Farming the plant is enjoyable when the harvest is bountiful. On the flip side, nutritional deficiencies may lead to low yields.

Nutritional deficiencies could be caused by mineral imbalances in the soil or plant. Like any other plant, the cucumber thrives on nutrient-rich soils.

Epsom salt holds the key as far as these nutrients are concerned.

It ensures your cucumber has enough Magnesium and Sulfur supply as lack of them leads to stunted growth.

In this article, we guide you on when and how to use Epsom salt for cucumbers to ensure high yields. Let’s take a deeper dive. 


Why Use Epsom Salt For Cucumbers?

Applying Epsom salt on your cucumber plants ensures healthy growth, greener plants, and better yields.

Epsom salt is a compound composed of Magnesium and Sulfur, abbreviated as MgSO4. 

Your soil lacks these elements when your plants show deficiency signs. Some of them include loss of vigor, poor growth, and low yields.

You should only use the salt if you notice the above symptoms and not use it regularly.

Nonetheless, it is beneficial to your cucumber plants in multiple ways.

Betters Uptake Of Nitrogen

Epsom salt contains Magnesium, the element responsible for increasing the uptake of Nitrogen and Phosphorus in plants.  

Corrects Chlorosis 

The above elements promote healthy plant growth by correcting leaf yellowing. This ensures more fruits are produced. 

Prevents Slow Growth

Cucumber plants growing in poor soils become stunted and weak. Epsom salt comes in handy in ensuring they have improved strength, growth, and high yields. 

Corrects Nutrient Deficiencies 

Applying Epsom salt to cucumbers enables you to fix the damage brought by nutrient deficiencies. The result is dark green foliage, dense growth, and more fruit production.

Prevents Root Shock 

Epsom salt is also helpful during transplanting. For example, if repotting your cucumber plant, you can mix one tablespoon in a gallon of water and add it to the soil to kickstart the growth.

Fastens Seed Germination 

Epsom salt is known to give seeds a better start during germination. Apply it to the planting hole before you plant your cucumber seed. 

epsom-saltThe Role of Magnesium And Sulfur In Cucumber Plants And Their Deficiency Symptoms


Magnesium in cucumbers and any other plant is essential for photosynthesis, during which plants synthesize nutrients using solar energy.

Therefore, Magnesium is vital for plant growth, and its lack or deficiency could prove detrimental to the plant.

Typically, Magnesium deficiency is more severe in soils that are sandy, light, or acidic. However, clay soils under intensive production might also suffer from Magnesium deficiency. 

Symptoms Of Magnesium Deficiency In Cucumber


  • Yellowing of older leaves. 
  • Interveinal chlorosis begins from the leaf edges moving inwards. 
  • Light tan burns in subsequent stages, which results in tissue loss. 
  • It also leads to necrosis and leaf shriveling. 
  • The entire leaf turns yellow in severe deficiency. 

Pay attention to your plants for these symptoms, which most likely surface from mid and late into the season. 

Excessive application of Potassium to your soil is also a significant cause of Magnesium deficiency in your soils. Apply compost manure or reduce Potassium application to correct the mineral imbalance.

Your soils could also become Magnesium deficient through leaching if you live in an area with excessive rainfall. 


Sulfur in cucumbers is crucial since it helps produce amino acids, enzymes, proteins, and vitamins. It supports plant growth and the formation of seeds.

Your cucumber’s ability to fight diseases is also dependent on Sulfur. 

Symptoms Of Sulfur Deficiency 


  • Pale green to yellow leaves. 
  • Restricted plant growth.
  • Younger leaves remain small and bend downwards. 
  • Necrotic spotting. 

When To Apply Epsom Salt To Your Cucumbers?

Add Epsom salt to your cucumbers when you spot signs of Magnesium and Sulfur deficiencies.

That means you need to look for any emerging symptoms constantly.

Ideally, you should have your soils tested to determine the mineral composition and what fertilizer additions you should make to your soil.

However, many gardeners find this more technical for them. For them, Epsom salt is a good alternative.

But the one downside with it is— high quantities can lead to soil toxicity. 

How Frequently Should You Apply Epsom Salt?


Ideally, your cucumbers should be getting all nutrients from the soil without the need for a fertilizer boost.

Under normal circumstances, with no deficiency symptoms, you can make one application during mid-season.

However, if you notice deficiency symptoms, follow the convention below:

  • If you are growing them in a vessel or pot, the recommended frequency of application is 4-5 weeks.
  • If you have planted your cucumbers in the garden, apply Epsom salt every 4-6 weeks.

Again you shouldn’t make frequent applications like a regular fertilizer because it will damage your cucumber plants. Too much Epsom salt on your cucumbers causes wilting.

How To Apply Epsom Salt?

This section guides you on the various techniques to apply Epsom salts to your cucumber plants. 

Applying Epsom Salt As A Solution

This is the most popular method most gardeners use. It involves adding Epsom salt to the water to form a solution.

You should pay attention to ensure you are getting the measurements right. A half tablespoon of Epsom salt is enough for half a gallon of water.

Stir the mixture well to make it effective. You want to make sure the Epsom salt dissolves fully in the water.

Pour the solution into a watering can and use it to water your cucumbers. This application should be enough to make the deficiency symptoms go away.

However, you can redo the application after 3-4 weeks if you still notice the symptoms. In some cases, the symptoms may not go away even after the second application.

If this is the case, do a soil test to establish whether a magnesium sulfate deficiency is present or some other nutrient is missing. 

Applying Epsom Salt As A Foliar Spray/Drench

Foliar spraying enables your plant to absorb nutrients via foliage and not the roots. It’s an effective method for boosting plant growth.

However, you shouldn’t stop regular watering if using the foliar spray, as your plants will still need their daily water dosage. Inconsistent watering will make the fruits taste bitter.

To get the measurements right, mix two tablespoons of Epsom salt with a gallon of water. Use a handheld spray bottle to apply the solution to cucumbers every month.

You could also schedule the application to be bi-weekly instead of monthly. For that matter, mix one tablespoon of Epsom salt with one gallon of water.

Be careful while spraying the solution as repeated applications in a short interval lead to leaf scorch. 

Sidedressing In Mature Cucumber Plants

mature-cucumberThough not a more popular method than the first two, side-dressing is also an easy and effective way of correcting nutritional deficiencies in your cucumber plants.

We recommend doing the application mid-season to give your plant a nutrient boost. During application, spread two tablespoons of the Epsom salt at the plant’s base. 

When Planting Your Cucumbers For The First Time

Another way of adding Epsom salt to cucumbers would be to use it during planting time.

Mix 1-2 tablespoons with the fertilizer, or add one tablespoon to the soil in the planting hole before seeding or transplanting.

Again ascertain your soil is lacking vital nutrients before using the salt. There will be no need for it if your soil is well-balanced nutrient-wise. 


You now know why Epsom salt is vital for your cucumbers.

Applying it in calculated amounts helps to correct the effects of Magnesium and Sulfur deficiencies. However, do proper soil testing before the application.

Use the salt on a need basis and not as a regular fertilizer. We hope you get healthy cucumbers this time round.

Epsom Salt for Cucumbers: When And How To Apply?

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